<ol xml:space="preserve">
<li>Choose the desired 
  
<a href="../../doc/Line_en.html#type">line type</a> in the options
toolbar.</li>
  
<li>Click the line entity to which the new line should be orthogonal.</li>
  
<li>Click the arc, circle or ellipse entity to which the line should be a
tangent. There are two possible solutions. When moving the mouse around, you
can see a preview of the tangent that will be created.</li>
</ol>
